<abstract xmlns="http://www.w3.org/1999/xhtml"><p>The field of microbial biotechnology has revolutionized the utilization of microorganisms to overcome the problems of environmental pollutions. The present study aimed to identify silver-tolerant isolates and screen their ability to synthesize silver nanoparticles for possible use as bioremediation agents. Seventeen bacterial isolates from soil collected from the Smokey Mountain landfill in Manila, Philippines, were found to tolerate 0.01 M AgNO<sub>3</sub> in the culture medium. Molecular and phylogenetic analyses using the 16S rRNA gene sequence identified the isolates as <italic>Bacillus cereus</italic>, <italic>Bacillus subtilis</italic>, <italic>Bacillus flexus</italic>, <italic>Bacillus thuringiensis</italic>, <italic>Alcaligenes faecalis</italic>, <italic>Achromobacter</italic> sp. and <italic>Ochrobactrum</italic> sp. The formation of silver nanoparticles was evident in the change in color of the reaction mixtures, and was detected through UV-VIS spectroscopy with absorbance peaks at 250-300 nm and 400-450 nm. Scanning electron microscopy revealed the aggregation of diverse shapes of silver nanoparticles with sizes ranging from 70 to 200 nm. The best silver nanoparticle-synthesizing isolates were <italic>Alcaligenes faecalis</italic> and <italic>Bacillus cereus</italic>. The results denote the promising microbial technology application of the 17 silver-tolerant isolates in combating the adverse effects of metals and other pollutants in the environment.</p></abstract>

The field of microbial biotechnology has revolutionized the utilization of microorganisms to overcome the problems of environmental pollutions. The present study aimed to identify silver-tolerant isolates and screen their ability to synthesize silver nanoparticles for possible use as bioremediation agents. Seventeen bacterial isolates from soil collected from the Smokey Mountain landfill in Manila, Philippines, were found to tolerate 0.01 M AgNO3 in the culture medium. Molecular and phylogenetic analyses using the 16S rRNA gene sequence identified the isolates as Bacillus cereus, Bacillus subtilis, Bacillus flexus, Bacillus thuringiensis, Alcaligenes faecalis, Achromobacter sp. and Ochrobactrum sp. The formation of silver nanoparticles was evident in the change in color of the reaction mixtures, and was detected through UV-VIS spectroscopy with absorbance peaks at 250-300 nm and 400-450 nm. Scanning electron microscopy revealed the aggregation of diverse shapes of silver nanoparticles with sizes ranging from 70 to 200 nm. The best silver nanoparticle-synthesizing isolates were Alcaligenes faecalis and Bacillus cereus. The results denote the promising microbial technology application of the 17 silver-tolerant isolates in combating the adverse effects of metals and other pollutants in the environment.

Screening of Silver-Tolerant Bacteria from a Major Philippine Landfill as Potential Bioremediation Agents

Biological Sciences Department, School of Science and Technology

Center for Natural Sciences and Environmental Research

Materials Science and Nanotechnology Research Unit, Center for Natural Sciences and Environmental Research

Ecological Chemistry and Engineering S

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

The field of microbial biotechnology has revolutionized the utilization of microorganisms to overcome the problems of environmental pollutions. The present...

Screening of Silver-Tolerant Bacteria from a Major Philippine Landfill as Potential Bioremediation Agents

Published Online: Oct 23, 2018

Page range: 469 - 485

DOI: https://doi.org/10.1515/eces-2018-0032

Keywords
microbial biotechnology, bioremediation, silver nanoparticles, silver-tolerant bacteria, biosynthesis, landfill

© 2018 Joan S. Adriano et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Screening of Silver-Tolerant Bacteria from a Major Philippine Landfill as Potential Bioremediation Agents

Published Online: Oct 23, 2018

Page range: 469 - 485

DOI: https://doi.org/10.1515/eces-2018-0032

Keywordsmicrobial biotechnology, bioremediation, silver nanoparticles, silver-tolerant bacteria, biosynthesis, landfill

© 2018 Joan S. Adriano et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
microbial biotechnology, bioremediation, silver nanoparticles, silver-tolerant bacteria, biosynthesis, landfill